Soy milk is mainly soy concentrate. Unlike whey, in which this form being more undenatured makes it healthier than the isolate version, soy concentrate has some stuff(can't remember if they're enzymes or just some other sort of substances) that actually prevent you from absorbing several nutrients. These are stripped away during the process to obtain soy protein isolate though, so soy isolate is actually healthier than soy concentrate. I know you're not drinking it for protein but just as a substitute for milk. A little bit is fine but I'd refrain from drinking large amounts of it. Maybe a glass(8 oz serving) or two a day I'm guessing.

"...that's the great virtue of the free market, of the private market. It enables people...who hate one another...who don't speak the same language...who would fight one another if they had the chance, to cooperate economically. We were able to deal with China when China was a communist state. Even though we thought that that was a terrible arrangement, we could still cooperate. And that's what markets enable people to do. They bring freedom with them."
- Milton Friedman

2. What does it do and what scientific studies give evidence to support this?

Soy protein provides a healthy way to get non-animal protein into your diet. It is great tasting, natural and can have a plethora of healthy effects on the body. It is ideal for high protein/low carb diets! It's valuable constituents include saponins, phytosterols, and isoflavones. This is one of the best things about soy protein! Saponins support healthy immune system function and combine with cholesterol to reduce it's absorption into the body through the small intestine. Phytosterols have also been shown to help maintain cholesterol levels already within normal range.
The anabolic isoflavones in soy (genistein and daidzein), not only have exhibited effects as powerful antioxidants, but have been shown to exhibit positive health benefits for both men and women.

Most concerns about soy have centered around the fact that it is a rich source of isoflavones, substances that mimic the effects of the female hormone estrogen. To determine what these plant-based chemicals might do, Steven Zeisel and his colleagues at the University of North Carolina at Chapel Hill fed megadoses of soy to men as part of a recent National Cancer Institute study.

Nipple discharge, breast enlargement and slight decreases in testosterone occurred with the megadoses. But "we still couldn't find anything that was serious, and we went up to doses that are probably 30 times what you could get from normal foods," Zeisel said. "I don't think that there are a lot of estrogenic worries. Your testicles will not shrink and you won't have massive breast enlargement" from eating soy.

Soy does indeed have estrogenic properties. It contains phytoestrogens, which are produced by plants and mimic the action of estrogens at the body's estrogen receptors. Because they are weaker than the estrogens that your own body produces, yet compatible with the estrogen receptors, they compete with estrogens at the estrogen receptor sites, and when bound to the estrogen receptor they block the effects of the stronger estrogens.

It has been speculated that a diet high in soy can have hormonally feminizing effects. This has almost no basis in fact, and really, makes very little sense. The beneficial effects of dietary soy are more related to the fact that it inhibits the action of estrogen, not that it has estrogenic effects itself. These inhibitory effects seem to decrease the risk of coronary heart disease (CHD) as well as breast and uterine cancer, but only when taken as part of a complete program.

Don't ask where I heard that; yes, I know I'm a dumbass. I just want to make 100% sure this is false.

just for the protocol: you are definitively not a dumbass. intelligent people ask and seek for knowlegde. dumb people do not want to improve their knowledge but like when their beliefs are being assured / confirmed by other bro's.

but to answer your question: no, I don't know of any study that provides evidense that soy may increase estradiol or estrone levels (the two main estrogens in the body).
they contain, however, isoflavones, that are often being referred to as "phytoestrogens". these phytoestrogens share some properties with the "real" estrogens, but do greatly differ in others. it depend on a hell of a lot of factors whether these phytoestrogens may actually exert an estrogenic effect or not. it depends on the tissue, on the distribution of different estrogen-receptor subtypes in different tissues, on the conentration of systemic and local estrogens and androgens etc etc etc....
There is some evidence that supports the assumption that isoflavones may have some protectie role against prostate-cancer.
on the other side, I have never heard of soy-induced gyno or anything like that.
IMO, the anti-androgenic / pro-estrogenic effects of soy are often overstated. otherwise, people with high soy intake would have much more signs of gyno and libido issues. but this is apparently not the case.

Always consult with a qualified healthcare professional prior to beginning any diet or exercise program or taking any dietary supplement. The content on our website is for informational and educational purposes only and is not intended as medical advice or to replace a relationship with a qualified healthcare professional.